Thread: embedded c code and volatile question

  1. #1
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    embedded c code and volatile question

    Good afternoon....
    I have a global int defined....It gets incremented in firmware (i++) each time an MSP430 wakes up and jumps into a GPIO Interrupt. Can someone tell me if I should have "volatile" modifier on it? I am always confused about this....Technically the ISR is a hardware piece however the act of the integer changing is NOT tied to anything other than the firmware incrementing it.

    Thanks
    Steve

  2. #2
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    You should probably have the volatile modifier, since from your description it appears that the variable is being changed asynchronously to your program.
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    Thank you.....Never heard the word asynchronously used with volatile but that I understand that...

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